RIVERSIDE – An operation to catch auto thieves and illegal gun traders in the Riverside area netted 42 arrests over four months, authorities announced today.

Operation ”Duck Pond” was conducted from March to June, resulting in the recovery of 44 stolen cars and the seizure of 26 illegal guns, police said.

Details about the multi-agency sweep were revealed during a news briefing at the Riverside Police Department’s Magnolia Station, where Chief Sergio Diaz was joined by Riverside County District Attorney Paul Zellerbach, representatives from the U.S. Bureau of Alcohol, Firearms, Tobacco and Explosives and Department of Homeland Security.

”Dozens of criminals were caught thanks to the extraordinary efforts and collaboration of the various law enforcement agencies,” Diaz said.

According to the chief, Duck Pond was initiated after investigators noticed a 10 percent spike in auto thefts throughout the city toward the end of 2011. He said anti-gang officers were deployed to penetrate suspected theft networks, leading to the identification of 10 to 12 crews that specialize in stealing autos.

Undercover officers purchased stolen cars, including luxury rides, for as little as $1,000, while illegally modified or stolen firearms, including AK- 47 semiautomatic rifles and sawed-off shotguns, were bought for an average price of $200, Diaz said.

He added that the gun trades occurred after informants and undercover investigators had gained the trust of suspects.

”This should be a lesson,” Diaz said. ”If you’re capering in the city of Riverside, you’re never going to know who you’re dealing with. Four months later, you might be picked up by the police.”

The total value of the recovered stolen merchandise — much of which was returned to the original owners — was estimated to be $500,000.

Altogether, 52 people, including five juveniles, were named in criminal complaints. Ten defendants, three of whom are underage, remain at large.

The wanted adults were identified as:

— Gene Anthony Castillo, 26;

— Alexandra Martinez Chavez, 26;

— James Haas, 39;

— Mario Hernandez, 25;

— Kathy McPhee, 40;

— Eric Navarro, 32; and

— Curtis Nixon, 19.

All of the defendants are charged with auto theft, drug or weapons- related violations. Nine of them have loose ties to area street gangs, according to prosecutors. McPhee and Navarro are facing federal charges, as well as six people already in custody.

”These people were in possession of serious weapons capable of maiming or killing,” said Central District of California U.S. Attorney Andre Birotte. ”We will hold these individuals accountable.”

Two defendants are three-strikers under state law and could face mandatory 25 years to life prison sentences if convicted, according to Zellerbach.

He noted that two other defendants were paroled from state prison early and returned to the county under Assembly Bill 109, the realignment measure enacted last year that makes certain ”low-level” offenders the responsibility of local authorities, who have to prosecute them in county court for parole violations and incarcerate them in county jails, sometimes for three or more years.

Zellerbach said that he was pleased a half-dozen of the most serious Duck Pond defendants were being prosecuted federally, assuring that if they’re convicted, their sentences will be lengthy, without the possibility of early release.

”There’s more custody time on the federal side. That’s where you get the biggest bang for the buck,” he said. ”You’ve got 52 individuals here, 43 of them with extensive criminal histories and backgrounds. We’re seeing the same people over and over again.”

Funding for Duck Pond — so named for the common law enforcement reference to a stolen car as a ”duck” — was provided in part by two California Department of Insurance grants totaling $10,000.